Locking means for folding laryngoscopes



July 21, 1953 Y c. s. cook ETAL 2,646,037

LOCKING MEANS FOR FOLDING LARYNGOscOPx-:s

5 Sheets-Sheet 1 Filed June4 23 1950 July 21, V1953 C. S. C OOKV .ET AL LOCKING MEANS FOR. FOLDING LARYNGOSCOPES 3 Sheets-Sheet 2 muv" ""f 9 Filed June 23, 1950 gum July 2l, 1953 LOCKING MEANS Foa AFOLDING LRYNcoscoPss Filed June 23, 1950 c. alcooK ETA.. 2,646,037

Patented July 21, 1953 gelata? LOCKING MEANS FOR FOLDING LARYNGOsoOPEs Charles S.' Cook, Sennett, and Harry L'. Becker, Auburn, N. Y., assignors to Welch Allyn, Inc., Auburn, N. Y., a corporation of New York `Application June 23, 1950, Serial No.V 169,918

The presentv invention relates to laryngo-f scopes, and Vmore particularly, to anl improved joint connectionbetween the blade and the handle of such type of instrument.

Laryngeal speculums are employed by mem-r bers of the medical profession for depressing the epglottis at thebase of the tongue, for illuminating the larynx for diagnostic or therapeutical purposes, for performing intra-nasal or intra-'trachael intubations, or for any other reason that requires access to and/or illumination of the posterior oral cavity, larynx, pharynx, or elsewhere, as vnecessary in each individuals case.

It is desirable in diverse cases to have a laryngoscope'that` is capablejof relative angular adjustmentof the handle and blade, so thatv theV therapist may approach the-patient from difierent angles` as may be required.

It is also desirable that the laryngoscope be foldable so as to` occupy a minimum of space when not in use, and that'various parts thereof be readily separable'for purposes of cleaning and sterilization. i Y

Therefore, it is an object of this invention to provide a laryngoscope having means for vary-V ing the angle of the laryngeal blade relativel to the handle of the instrument, and positively lock-f:

12 Claims. (01.412856) ing the same in the various positions ofangular 1' adjustment. l i Y Another object of this invention is to provide a laryngoscope that is so constructed as to permit the laryngeal blade to be moved from any of Vits various positions of angular adjustment to a position closely adjacent tothe handle of the instrument.

A further object of the invention is tol provide a laryngoscope that is so constructed as to permit the blade section thereof to bereadily and simply detached from the handle section.

A still further object of the invention is to provide means associated with the relatively adjustable and separable blade and handle portions,` for automatically effecting energization of the light source, usually mounted at one end of` l the laryngeal blade, when the blade` is in an operative position relative to the handle, and

conversely, effecting de-energization of saidlight y sourceincident to movement of the blade to an inoperative position closely adjacent to the;v

handle of the instrument. p

These and further objects and advantages ascribed to the novel joint or connection between the handle and blade portions of the instrument of this invention, will become apparent from the following detailed description anddrawv 2 Y fr ings forming a part of this application, and the novel features thereof dened in the appended claims.

In the drawings: Y f

Figure 1 is a View in side elevation of a laryngoscope embodying one form of improved hinge joint of this invention, and showing in dottedA lines the various positions of adjustment of the blade, with the joint cap removed;

Figure 2 is a fragmentary view in end elevation ofthe joint and adjacent parts of the instrument of Figure 1; A

Figure 3 is an enlarged View in vertical section as taken on the line V3 3 of Figure 1, certain fof the parts being shown in elevation;

Figure 4 is a View in vertical section taken on the line 4 4 of Figure 3;

Figure 5 is an enlarged view in horizontal section taken on the line 5-5 of Figure 1, with part of the plunger pin shown in plan, and other parts of the pin broken away;

Figure 6 is a view invertical section as taken on the line 6-6 of Figure 2;

Figure 7 is a compositevi'ew of the two separable joint members in a disjointed condition, and showing the inner,A complementary interlockingly engageable portions thereof in elevation and in position for inter-engagement when they are turned to face each other;

Figure 8 is an exploded View of the joint construction, with parts of the female section thereof shown in vertical section;

Figure 9 is a View in vertical section, taken on the line 9 9 of Figure 10, of a modied form o f y a joint according to this invention, with a portion of the male part broken away;

Figure 10 is a View in vertical section as taken Y on the line lil-I0 of Figure 9, with certainof the parts shown in elevation andothers broken away; I i

Figure 11 is a composite view of the two separable joint members, of the modied 'form shown in Figure 9, with the joint members in a dis-V jointed condition, and showing the inner, complementary interlockingly engageable portions' thereof in elevation, and in position'for interl engagement when they are turned to face each other;

Figure 12 is a view in top plan of the male portion of the modified joint of Figuresv 9 to 11; and

Figure 13 is a view in perspective of the positioning ring which forms a part of both forms of this invention.

Like reference characters designate correspondng parts in the several figures of the drawings, wherein the laryngoscope as seen in Figure I comprises a handle member l and a blade member 2, which members are interlockingly, detachably and adjustably interconnected by means of the novel joint construction 3, which will hereinafter be described in detail.

Suitably attached adjacent to one end of the.

laryngeal blade 2 is a head member 4 which is generally frusto-conical in shape, the free end or this head member forming the female portion of the joint 3, and the head member and blade forming a blade unit.

The handle I of the instrument is adapted to receive an upwardly tapering basemember 5, the free extremity of which forms theV male portion of joint 3, and the handle and base portion forming a handle unit.

The details of construction of the adjustable and separable joint 3 will now be described.

The free end of the hereinbefore mentioned head member 4 is provided with an enlarged hollow cylindrical joint member 6 having theaxis of the cylinder disposed at right angles to the axis of the head member 4, the cylindrical member 6 being oiset laterally, whereby one face thereof is substantially flush with the central axis of the head as best shown in Figure 8.

Internally of the cylinder 3 and towards the inner end thereof the opening therethrough is reduced in diameter to form a shoulder 'I, and an opening or bore of a lesser diameter 'I'.

Suitably secured in close itting relationship to the shoulder I is a locking or positioning ring 8, said ring being provided with a plurality of radial, spaced, diametrically opposed'locking or' positioning recesses 9 therein,y and a pair of diametrically opposed radial slots therethrough as indicated at IIJ.

Inwardly spaced fromY the shoulder 'I of the cylindrical member B, the inner face of the reduced bore 'I' is provided with an annulargroove II and a pair of diametrically opposed slots I2 entering the groove, these slots I2 extending longitudinally to the inner face of the cylindrical member 5, and forming a so-called bayonet slot.

A closure cap 25 is suitably positioned in the I open outer end of the cylindrical portion', as by a tight slip t, as indicated at 6.

Detachably interconnected with the hereinbefore described female portion 6 of the joint 3, and angularly adjustable relative thereto, is a male portion of the joint, which comprises a second substantially hollow ment I3 at the upper end of the base member 5. This cylindrical part I3 also has its central axis disposed at right angles to the axis of the base member and is laterally offset therefrom so as to have the inner face of the cylinder substantially flush with the axis of said base member, as best shown in Figure 8.

Extending coaxially with and inwardly from the cylindrical portion I3 is a second cylindrical portion I4 of reduced diameter, the two coaxially extended cylinders having` a common bore or opening therethrough as indicated at I5.

The base member 5 is provided with a shoulder 5' vertically spaced from the cylindrical projection I4 a su'lcient distance to permit of receiving the lower portion of the cylindrical member 6 therebetween, upon assembly of the respective joint parts.

The reduced cylindrical projection I4 is .of a size to be closely but freely rotatably received cylindrical enlargein the reduced portion I of the head section 6 of the joint, and is provided with a pair of diametrically opposed, radially projecting pins I6 adapted to cooperate with the groove II in the opposite member 6 for preventing relative lateral play between the two sections when angular vadjustmentof the joint is being eiected.

The reduced cylindrical member I4 is also provided with a pair of radial, diametrically opposed slots Il extending substantially the full length of the member.

The outer or righthand end, as seen in Figure 8,v of the cylindrical joint member I3, is provided with an annular groove or recess I8 adapted to receive therein the inner convolution of a compression spring I9.

A pin or plunger 2i) of a diameter slightly less than the bore I5 of the base section 5 is received in the bore and is shiftable endwise therein, said pin 20 being provided at one end thereof with a locking or positioning key 2l and a second key 22 cooperatively engageable with the slot I'I in the member I4 for preventing rotation of the pin 20 in the bore I5, as will be hereinafter more fully described.

The other end of the pin 2l! is provided with a reduced, screw-threaded portion 23 engageable for purposes of assembly With the tapped projection 24 of a plunger button or cap 25. The cap 25 has an annular recess 26 therein for accommodating and seating the compression spring I9. A chordal recess 21 is located in the side wall of the cap 25, and will be more fully described as the description progresses.

The instrument is provided with suitable means for energizing a light bulb 28 carried at the extreme outer end of the blade 2, when the blade is in any of its various operative positions, and for deenergizing the light bulb when the blade is in its inoperative position or in the position permitting of separation of the adjustable joint, the operative positions being designated in Figure 1 of the drawings as A, B and C, and D designating the disengaging or separable position, and F designating the folded or inoperative position.

VThe means for effecting the energization or deenergization of the light source 28, includes a suitable number of ashlight batteries 29 carried in the handle I, as is customary in the art,

i, the handle being iitted to the base member 5,

as at 33.

Electrical contact with the batteries 29 is made by means of a contact member 3l suitably positioned in a vertical bore 32 in the base member 5 and insulated therefrom, so as to be engageable with battery contact 33. An opening or passage 34 is also provided in the base member 5 and extends upwardly through the cylindrical portion I3 thereof, as best seen in Figure 6. Electrical conductive insulated wire 3I extends from the contact 3l through the passage 34 and is connected to a contact shoe 35. This contact shoe 35 is mounted in an insulating member 35 suitably secured as by means of screws 31 in a groove 38 formed in an arc of 39, contact shoe 35 yand their respective' insulating blocksand fasteningv means are so located in the head t and thebase 5 respectively of the assembly thatthey do`not interfere in any way with the lateral separation of the two parts which form the joint 3.

Connected to the ball contact assembly 39, passing upwardly through the head 4 is a second section of conductive, insulated wire 44, which is passed ltothe exterior of the head member in the area adjacent the juncture of the head 5 and the blade 2, as at 45 (Figure 1) and then leads through a tube 44' to the light28. Ground iov contact for the other side of the circuit is made through the metal parts of the instrument.

While the instrument of this invention has been shown and described as carrying batteries in the handle, it is within the purview thereof to have a-house current connecting means carried by the Ahandle in lieu of the batteries.

The assembly of the hereinbefore described components will now be described.

` The pin 2U is passed through the bore I5v in I the basey portion 5, the key 22 slidingr into the slots I'I of the member I4 and preventing relative rotation of these parts. spring I9 is then positioned in the annular groove I8 in the cylindrical member I3 and the plungerV button .or cap is threaded into position on the pin 20.

'The outer diameter of the annular recess 26 in the cap'25 is preferably of a size whereby the cap may overlap the marginal edge of the cylindrical member I3, as seen in Figure 3. The

arcuate recess 21 in the edge of the cap 25 is.r

provided for permitting of relative reciprocating movement of the pin 2n relative to the base 5 without interference from the cap, as is apparent in Figures 3 and 10.

, The mating joint member G, forming a part of the' head 4, may now be connected with the base joint member Ill when the parts are in a position relative to each other as designated D in Figure l, the key 2i passing through the slots I0 in the locking ring 3 and the pins I2 into the groove II.

Now it is apparent that sufiicient pressure applied inwardly on the plunger button will shift the pin 2t laterally in the direction of pressure to a point where the positioning or locking I6 entering the slots f The compression key 2| is in a position laterally past the outer face of the locking ring 8. Clockwise rotation of the head 4 relative to the base 5, as viewed in Figure 1, will cause corresponding rotation of the key ZI and the pins I6 relative to the locking ring 8 and the groove II respectively, this clockwise relative rotation being limited by the abutment of the blade 2 against the handle I, as seen in position Fv in Figure 1. The positioning or locking key 2l will now be out of alignment with the slots IB in the locking ring, and therefore the joint is positively secured against relative lateral disconnection.

Relative lateral play between the two jointare so positioned when the assembly is in posin tions D and F that the ball 3S isin contact with vinto interengaging relationship,

therinsulating member 36. Therefore no ener-- gization of the lamp 28 is effected-in these respective disengaging and inoperative folded positions.

Upon reverse or counter-clockwiserelative rotation of the head and base members, the posi'- tioning key 2|, incident to therelease of pressure on the button 25, selectively seats in one of the grooves 9 in the locking ring 8, thereby locking the blade and handle sections of the laryngoscope against inadvertent relative rotation in either direction.

It is apparent that upon counter-clockwise rela-A tiveY rotation of the head and base, that the ball contact 39 will ride up on the contact shoe .35, thereby energizing the lamp 28 in all of the operative positions of the instrument. Y v

The modified form oi the invention shown in Figures 9 through l2 is the same in function as the preferred formhereinbefore described, and the construction of the respective elements of the laryngoscope are identical in most respects, and therefore have been given the same reference characters, except for those modified parts which have been primed, and will now be described.

The only difference between the previously de? scribed form and the modification is that, as best seen in Figures 11 and l2, the groove l i' and slot I2 are formed in the peripheral surface of the reduced cylindrical extension `I l of the base member 5. Instead of being an annular groove, the

lgroove i I constitutes only an arc of the annulus,

the opposite ends of the groove being cooperative with the pin i6', carried by the reduced portion a of the head section li, to effect a limit'stop, whereby the degree of relative angular adjustment of the joint is limited by the length of said groove. The extremity i5 of the groove IIv is so located as to form a stop when' the head and base sections are in axial alignment,as seenl in Figure 9. Y Y

It will be readily apparent that laryngeal blades of diierent types and/or sizes may be easily and quickly interchanged for use with a common base or battery handle when the blade sections and This-is particularly desirable since these laryngoscopes are usedfor patients of various ages rang-f ingfrom small children'to adults. in the use of the laryngoscope,

in the relative position designated D -in Figure 1', slip the mating portions of the two joint sections apply thumb pressure to the plunger button or cap 25, and ro'- tate the joint parts relative to each other to the desired selective operating position of the blade, the light being automatically energized when the contacts 39 and 55 are brought into contacting relationship incident to the relative rotationof the base and head sections. Upon release of the thumb pressure aforesaid, the blade is positively and automatically locked in position by -virtueof the locking key 2i seating in one of the grooves Si of the locking ring ii.

While the specic details have been shownV and described herein, our invention is not conned thereto as changes and alterations may be made without departing from the spirit thereof as dened by the appended claims'.

We claim:

l. A laryngoscope, comprising a handle section, a blade section, and means hingedly connecting the sections, said means Ycomprising a hinge joint which includes complemental, relatively rotatable it is only necesl sary to hold the blade section of the instrument blade sections and separably interengaged with each other with said blade section angularly adjustable relative to said handle section, cooperatively interengaged means within said hinge joint for positively locking said blade section in selec.- tive adjusted positions and for interlocking said sections together in said adjusted positions, said cooperatively interengaged means being disengageable when said sections are in one predetermined position relative to each other for separating said sections, and cooperative means in said hinge joint interlocking the sections against relative lateral movement while the sections are being relatively angularly adjusted.

2. A laryngoscope, comprising a handle section, a blade section, hinged interconnecting means therebetween, said means comprising a hinge joint and including complemental, relatively rotatable members carried by the respective handle and blade sections and separably interengaged with each other with said blade section angularly adjustable relative to said handle section, cooperatively interengageable means within said hinge joint for positively locking said blade section in selective adjusted positions and for interlocking said handle blade sections together in said adjusted positions, said cooperatively interengaged means being disengageable when said sections are in one predetermined position rela- 'J tive to each other for separating said sections, cooperative groove and pin means in said hinge joint for preventing relative lateral movement between said sections while the sections are being relatively angularly adjusted.

3. A laryngoscope as defined in claim 2, wherein the cooperative groove and pin means in said hinge joint for preventing relative lateral movement between said sections, comprises pin means carried by one of said complemental members, and a groove in the other of said complemental members.

4. A laryngoscope as donned in claim 2, wherein the cooperative groove and pin means in said hinge joint for preventing relative lateral movement between said sections, comprises a pair of radially extended pins on one of said complemental members, and an annular groove in the other of said complemental members.

5. A laryngoscope as dened in claim 2, wherein the cooperative groove and pin means in said hinge joint for preventing relative lateral movement between said sections, comprises a radially directed pin on one of said complemental members, and an arcuate groove in the other of said complemental members.

6. A laryngoscope as defined in claim 2, wherein the complemental, relatively rotatable members comprise a female part substantially cylindrical in form, a mating part having a cylindrical enlargement and a coaXially extended reduced cylindrical projection insertable in the female part aforesaid, said cylindrical enlargement and cylindrical projection having a common bore therethrough, and wherein the cooperatively interengaged means comprises a plunger pin reciprocatably positioned in said common bore, means for preventing rotation of said plunger pin in the bore, a locking ring secured internally of the female part aforesaid, said locking ring having a plurality of radially disposed grooves therein, a key carried by one end of the plunger pin aforesaid and engageable in said radially disposed grooves for eiecting positively locked adjustable positioning of the complemental, rela- CII tively rotatable members, and means normally urging said key into engagement with said radially disposed grooves.

7. A laryngoscope as deiined in claim 6, wherein the means for preventing rotation of the plunger pin in the bore comprises a slot in one of the complemental members extending radially from said bore, and a key carried by said plunger and pin and slidable in said slot.

8. A laryngoscope of the class described, comprising a head member, a base member, an angularly adjustable, separable hinge joint interconnecting said head and base members, said hinge joint including complemental, relatively rotatable members, a reciprocatable pin passed through said complemental members and having means cooperative with one of the complemental members for preventing relative rotation thereof while permitting reciprocatable movement of said pin, a locking ring in the other of said complemental members, a locking key carried by one end of the pin, said key being interlockingly engageable in at least one position with said locking ring for eiiecting positively locked angular adjustment of the head and base members aforesaid, complemental groove and pin means in the respective complemental members aforesaid for preventing relative lateral play between said complemental members during relative rotation thereof, slots in the locking ring and slots also in the complemental member having the groove aforesaid, for passage of the locking key and complemental pin respectively therethrough, thereby permitting of lateral separation oi the relatively rotatable, complemental members when in a single predetermined position relative to each other and preventing said separation in every other relative position, and circuit closing means carried by said relatively rotatable members adapted for closing a circuit automatically upon relative rotation of said members in one direction, and opening said circuit automatically upon reverse relative rotation thereof to a predetermined position.

9. An angularly adjustable and separable joint connection, comprising a pair of relatively rotatable, complemental members, means separably connecting said members together, one of said members being provided with a locking ring and the other of said members being provided with a shiftable hinge pin therethrough, said hinge pin having means for selective inter-engagement with said locking ring in a plurality of positions and positively locking said joint in the desired angularly adjusted position, and means for biasing the means on the hinge pin into inter-engagement with said locking ring, said locking ring being provided with an opening therethrough for permitting disengagement of said means on the hinge pin and said locking ring with attendant lateral separation or said complemental members in a single predetermined position while preventing separation in every other relative position of the members aforesaid.

i0. An angularly adjustable and separable joint connection as dened in claim 9, wherein the hinge pin has means slidably inter-engageable with its complemental member for preventing relative rotation `oi the pin with respect to its complemental member.

l1. An angularly adjustable and separable joint connection, comprising a pair oi relatively rotatable, complemental members, one of said members being provided with a locking ring and the other of said'members being provided with a hinge pin therethrough, said hinge pin having means for interlocking inter-engagement with said locking ring in at least one position and positively locking said joint in such angularly adjusted position, meansfor biasing said means on the hinge pin into inter-engagement With said locking ring, a pin-receiving bayonet slot in one of said members and a pin on the other member interengageable in said bayonet slot for preventjing relative lateral play between said members when they are being rotated relative to each other, said locking ring being provided with means for permitting lateral separation of said complemental members ina single predetermined position, while preventing separation in every other relative position of the members aforesaid.

12. An angularly adjustable and separable joint connection, comprising a pair of relatively rotatable, complemental members, one of said members being provided with a locking ring and the other of said members being provided with a hinge pin therethrough, said hinge pin having means for selective interengagement With said locking ring in a plurality of positions and positively locking said joint in the desired angularly adjusted position, means forkbiasing said means on the hinge pin into inter-engagement with said locking ring, a pin-receiving bayonet slot in one of said members and a pin -on the other member interengageable in said bayonet slot for preventing relative lateral play between said members when they are being rotated relative to each other, said locking ring being provided with means for permitting lateral separation of said complemental members in a single predetermined position, While preventing separation in every other relative position of the members aforesaid, and electrical circuit closing means carried by the complement-a1 members aforesaid and adapted to make electrical contact incident to relative rotation of the members in one direction past a predetermined position and conversely to break said electrical contact incident to reverse relative rotation of said members past said predetermined position.

CHARLES S. COOK. HARRY L. BECKER.

References Cited in the le of this patent UNITED STATES PATENTS France June 8, 1931 

